1. Field of the Invention
The present invention relates to a loaded composite emulsion based on a bituminous binder and one or more resins in order to provide a road surface protection layer against petroleum derivatives. The present invention is useful in civil engineering and in the military field.
2. Discussion of Background Information
Materials soluble in organic solvents have been used in the manufacture of road surface layers, thus rendering the coating thus formed poorly resistant to kerosene, to organic oils and to carbohydrates in general. Still, the road surface layers are liable to receive such substances that may be damaging for them. It is therefore desirable to use materials whose resulting coatings have excellent chemical resistance to organic oils, to kerosene and to carbohydrates in general, especially for coatings used for roads, industrial floors, parking areas, petrol station garages, airport runways, and the like.
Most prior art emulsions, formulated to have chemical resistance, contain a large proportion of tars or other products derived from coal and are recognized as being toxic. Toxic products, in the context of the present invention, refer to products that, because of the carcinogenic substances that they contain, must be subject to classification and labelling according to the regulation currently in use in France.
To this day, the products based on bitumen and resin contain a third component, which is a solvent whose vaporization after hot application is detrimental to the environment.
EP 0 231 477 describes an epoxy resin mixed with a bitumen emulsion and a crosslinking agent to improve its permeability to water steam and its metal adhesion. But it is a compound intended to modify the characteristics of the resin, that is in the form of a paste which has not been emulsified and is therefore difficult to handle.
French Patent No. 2,366,342 suggests a compound with the same restraints.
EP 0 695 788, which belongs to the applicant, teaches a composite emulsion that confers the formed coating with excellent chemical resistance to organic oils, to kerosene and to carbohydrates in general, without any toxicity during manufacture, during application, or during the duration of its service. Also, the coating is free from solvent and any other substance liable to be harmful to the environment. This composite emulsion can be cold applied onto a road surface in progress. This composite emulsion for road carpet or running surface is,obtained from a first emulsion comprising a bituminous binder and a crosslinking agent and from a second emulsion comprising a resin. The bituminous binder and the resin are each used in the form of a water emulsion.
However, the behavior of such a composite emulsion with the course of time and/or when it is subject to environmental cycles, such as temperature, humidity variation, etc., and to traffic, is not optimal. The coating layer peels away from the support and cracks in several locations. These defects bring forth degradation of the support such that it becomes then exposed to the environment directly. Moreover, the residual black color of the composite emulsion applied as a thin film evolves with the course of time, notably further to the attack of solar ultraviolet beams due to the presence of epoxy resin, i.e., the film becomes lighter in color, yellowish, fades, and sometimes translucent. The time-related evolution of the emulsion may cause problems in certain situations.
The present invention suggests remedying these shortcomings by using a bitumen/resin composite emulsion for a road surface protection layer resistant against the attacks of petroleum derivatives, a layer made by mixing a first emulsion comprising at least one resin with a second emulsion comprising a bituminous binder and a resin crosslinking agent. This type of protection is also called A.K.
The present invention relates to a bitumen/resin composite emulsion for a road surface layer to protect the layer against attacks from petroleum derivatives, wherein the composite emulsion is produced by mixing a first emulsion comprising at least one resin with a second emulsion comprising bituminous binder and resin crosslinking agent to form the bitumen/resin composite emulsion. The bitumen/resin composite emulsion further comprises a filling agent selected from filler, sand, fine sand, or mixtures thereof, wherein the filling agent is defined by standard XP P 18-540.
The filling agent can range from 10 to 90% by weight of the total weight of the bitumen/resin composite emulsion. The filling agent can preferably range from 25 to 50% by weight of the bitumen/resin composite emulsion. The filling agent can be siliceous.
The bitumen/resin emulsion can further comprise a pigmentary preparation. The ratio of the pigmentary preparation can range from 0.05 to 2% by weight, the percentage weight being calculated with respect to the weight of bitumen/resin composite emulsion and the weight of the filling agent.
The filling agent can be incorporated into the second emulsion that contains the bituminous binder. The filling agent can be incorporated into the first emulsion that contains the at least one resin. The filling agent can be incorporated into the bitumen/resin composite emulsion.
The at least one resin can comprise an epoxy type resin. The epoxy type resin can be selected from liquid epoxy resins or emulsified solid epoxy resins. The resin crosslinking agent can be injected at the ratio of 1.7 to 1.1 stoichiometrically with respect to the bitiminous binder.
The at least one resin in the resin-containing emulsion can be up to 80% by weight of the resin-containing emulsion. Alternatively, the at least one resin in the resin-containing emulsion can be from 50 to 80% by weight of the resin-containing emulsion.
The present invention also relates to a road having a surface coating comprising one or more layers of the bitumen/resin emulsion as set forth above, wherein each of the one or more layers has a thickness ranging from 0.1 to 2 mm.
The present invention also relates to a bitumen/resin composite emulsion for a road surface layer to protect the layer against attacks by petroleum derivatives, the bitumen/resin emulsion being produced by mixing a first emulsion comprising at least one resin with a second emulsion comprising bituminous binder and resin crosslinking agent to form the bitumen/resin composite emulsion. The bitumen/resin composite emulsion further comprises a filling agent and pigmentary preparation, wherein the filling agent can be selected from filler, sand, fine sand, or mixtures thereof. The filling agent is defined by standard XP P 18-540, wherein the filling agent can range from 25 to 50% by weight of the bitumen/resin composite emulsion. The filling agent can-be siliceous.
The ratio of the pigmentary preparation can range from 0.05 to 2% by weight, the percentage weight being calculated with respect to the weight of bitumen/resin composite emulsion and the weight of the filling agent. The resin in the resin-containing emulsion can be from 50 to 80% by weight of the resin-containing emulsion, and can comprise an epoxy type resin selected from liquid epoxy resins or emulsified solid epoxy resins.